The generic DE 103 00 298 A1 discloses a device for purification of exhaust gases for an exhaust gas line of an internal combustion engine which has a double-flow exhaust gas line, each segment of the line having a NOx storage catalytic converter, a NO2 producing catalytic converter, a SCR catalytic converter and a metering device for metering of a reducing agent. This structure is designed to ensure that the SCR catalytic converter with the stored ammonia can reduce the nitrogen oxides which are still contained in the exhaust gas flow downstream from the NOx storage catalytic converter, with the ammonia being simultaneously oxidized. A separate sensor is assigned to each of the catalytic converters in each of the component exhaust gas lines. This structure which is shown in FIG. 5 of DE 103 00 298 A1 is very complex and is thus expensive to produce both in terms of component engineering and also control engineering.
A similar structure is also disclosed in EP 1 055 806 A2 in which the liquid reducing agent is supplied in a controlled manner from a storage tank via metering valves which are assigned to each component exhaust gas line of a double-flow exhaust gas line. A structure which is essentially identical thereto is known from DE 199 57 539 A1 (FIG. 3). These structures thus likewise have the aforementioned disadvantages.
In contrast, the object of this invention is to make available a device for purification of exhaust gases for the exhaust gas line of an internal combustion engine, by means of which exhaust gas purification can be implemented in a structurally simple manner with high operating reliability.